1. Field of the Invention
This invention relates generally to database management and particularly to a computer program product for database query optimization.
2. Description of Background
The use of programs such as “database management systems” (DBMSs) to search or “query” collections of data or “databases” (DBs) in numerous forms, such as text, graphics, audio, or video, is very popular in most industries throughout the world, including financial, goods and services, governmental, medical, and technological industries. For a long time, such users have developed their DB programs internally, for example, with the assistance of programmers who are employees, contractors, consultants, etc., and this in-house development has typically provided customized, well performing programs. However, the increasing costs of utilizing specialized programmers and the often significant changes in DB program function requirements, for example, due to business changes and technological advances, has resulted in a new trend of DB program users relying more on DB programs that are pre-developed by independent software vendors (ISVs).
The use of such ISV DB programs offers advantages such as improved costs and the flexibility to quickly address changing function requirements (e.g., by purchasing other packages). However, there is a tradeoff of the inability of users to modify ISV DB programs for optimal query performance, since the programs are usually provided in an uneditable format such as object code only (OCO). For example, since many ISV DB programs are pre-developed for multiple usage on various computer platforms, they include program code or “structured query language” (SQL) in generic formats or “statements” that can sometimes cause less than desirable performance, such as slow execution of DB queries, depending on specific user needs and/or DB characteristics. Although there are tools available to DB administrators to help identify problem causing SQL statements that are provided by ISV DB programs in an effort to accommodate their use, there is still the inability to replace the problem statements in the programs to efficiently resolve undesirable query performance. As a result, users typically rely on an often speculative, time consuming process of persuading the ISV to modify the DB programs accordingly. Thus, it is desirable to overcome this inability to efficiently optimize DB query performance through the replacement of problem causing SQL statements when using ISV DB programs.